Lubricant



Patented Feb. 16, 1954 LUBRICANT Sabine Hirsch, Minneapolis, Minn., assignor to Cargill, Incorporated corporation of Delaware Minneapolis, Minn., a

No Drawing. Application April 15, 1949, Serial No. 87,839

12 Claims. (01. 252-45) This invention relates to lubricants and to processes of preparing them. It refers to lubricants consisting of a mineral oil and a soap which has been made from oxidized hydrocarbons. Moreover, the invention refers to lubricants in which the soap is made from oxidized hydrocarbons which are compatible with vegetable or animal fats, or fatty acids, so that mixtures of them could be used for lubricants which are intended to have special properties.

Heretofore, it has been th general practice to utilize natural fats or fatty acids, or mixtures thereof, of animal or vegetable origin in making soaps for greases. The better quality greases are made from refined or hydrogenated fats or fatty acids, but the bulk of the grease is made from low-grade animal fats which have a bad odor and a high percentage of rancidity. Sometimes the odor can be masked by cheap perfume, but this will disappear in time and leave the objectionable odor in the grease, when the same is stored for a longer time. Furthermore, these low-grade fats are not always uniform in quality, and therefore, the grease maker is never certain of being able to produce greases of uniform quality. But even when refined fats or fatty acids are used, it is the general practice to add anti-oxidants to prevent rancidity and oxidation.

In the present invention where oxidized hydrocarbons are used for the soap base, the greases made of this product are always of uniform quality because the oxidation by which these hydrocarbons are obtained can be directed always 11) the same way. Any saponification number desired can be obtained. Thes oxidized hydrocarbons never get rancid or obtain an objectionable odor so that lubricants made from soap base using them do not need the addition of antioxidants.

A particular feature of the present invention is the fact that lubricants can be made from oxidized hydrocarbons, as such, without the addition of any animal or vegetable fats or fatty acids. The lubricants so obtained have very great stability, a low break-down when worked, and a very good oiliness, that means they have the property to wet metal surfaces well and leave on the metal a film which is not readily removed. Soap bases made from this type of oxidized hydrocarbons are compatible with paraflinic or naphthenic base mineral oils. Oxidized hydrocarbon mixtures are very easily saponified in water as Well as in an all media, which results in finished greases of good quality in a short time. Most greases can be kettle finished, thus. avoiding the multiple stepsof providing a homogeneous grease. It has been found, however, that oxidized hydrocarbons when used, as such, in the soap for grease making show much better stability and have a much smaller break-down percentage in the mechanical worker than greases made with soaps in which mixtures of natural fats and oxidized hydrocarbons have been used. 7

An object of the invention is to provide a lubri cant composed of a soap made from oxidized hydrocarbons, as such, and a mineral oil to form a grease which has great stability.

Another object of this invention is to provide a lubricating grease composed of a major portion of mineral oil and a minor portion of soap made of oxidized hydrocarbons, as such, to form a grease which under standard break-down testing conditions has a break-down of less than 10%.

Another object of this invention is to provide a lubricant grease consisting of a major portion of mineral oil and a minor portion of soap made from a mixture of oxidized hydrocarbons and animal or vegetable fats, or fatty acids, or mixtures thereof, to form greases of special desired properties.

A further object is to provide a soap base for lubricant greases in which the oxidized hydrocar bons are saponified with more than one neutralizing agent so as to form a multiple soap base;

In carrying out this invention, a hydrocarbon or a hydrocarbon mixture, which at normal tem-* perature and normal pressure is liquid or solid, or of high viscosity, is heated in a kettle with stirring facilities to a temperature preferably of 255 F., but not much higher than 300" F. In this heated mass is introduced a gas containing oxygen and carrying a minor percentage of moisture. To accelerate the oxidation, an oxidation catalyst is used, as well as a minor percentage of a metal--. lic per-salt in an emulsion of water and an oleagineous material, andso forming an emulsion of the whole reaction mass during the time of the oxidation process. The method of oxidizing the hydrocarbons is fully described and claimed in my prior Patent 2,391,236, granted on December 18, 1945. When the oxidation has reached the de sired saponification number the oxidized hydrocarbons are taken out from the kettle and washed and filtered. The washing of this product can be made with hot water, acidulated water, or salt water. After filtering the product is ready to be used for soaps and lubricants.

GENERAL PROCEDURE I Into a grease kettle is charged 200 parts oflOU maintained until most of the water has evap'oe rated. When all of the water is gone the temp er-.

ature is raised to about 280 F. and then to this basic grease mixture, 200 parts OLpre-heated.

heavy naphthem'c mineral oil of aviscosity'oi240 SUS at 210 F. is added step by step. The temperature of 280 F. is maintained until all the heavier mineral oil is entirely incorporated in the grease. The grease is then ready to be poured into containers. This can be done at .280" EX or if desired the grease can be stirred down to a lower temperature and then poured:.-into.containersready for use.

In order that the lubricant may have a stable consistency after a considerable amount :of working; it: is .necessary that the hydrocarbons, which areialways heavier aliphatic hydrocarbons varying inmonsistency from. liquid -.to solid at, normal temperatures, be substantially oxidized;.and:that the aunfiapon-ifiable materials remain in: the ,mixtunes The, hydrocarbon used as the startingmaterialjmay andwill .beof varyinsnatures, but when oxidized to;produee saponification numbers in therrange of about 155-190, the .PIOduCttWiH have been oxidized to :such an -extent that when formedwinto soapv ,produces lubricants .of stable consistency that will, withstand vigorous prolonged working; without :breakdown.

The break-down test referred tohereinafter is a estandardtest adopted by-the A.- .S; T. M.

EXAMPIE'NC. 1

Sodium grease Theprocedure.is .described in thegeneral de-. scription.

Used are:

200.parts of :100 -SUS at 100 F.- naphthenicmin- :eral'oil 100 "parts of oxidized' hydrocarbon mixtur sap.

No; about 159 12 parts:of NaOH in 12 parts of water 200 .parts of heavy naphthenie mineral oil 240 SUS fat 21'0" F.

Thisis' a. smooth, non-fibrous sodium grease oi homogeneous texture, having good. odor. There isno indication of syneresis aitera long period of storage at temperatures over 90 F. Field tests onhigh' speed bearings running over 1700 R. P; M. under full load showed verygood'lubrication and cool performance.

Consistency:

At fiflstrokes 288 at 77 F. At 5000.strokes 300 vat.'7'7 F. This is abreak-downof-4 Dropping. point 'by Ubbelohde method more than e150"v F.

EXAMPLE NO. 2.

Calcium grease The procedure isdescribed in. the general .description. Used are:

200 parts of *100 SUS"at100 F. naphthemc mineral. oil.

parts of oxidized hydrocarbon mixture sap.

No. about 155.

10.5 parts of Ca(OH)z in 15 parts of water.

A mixture of:

100 parts of 100 SUS at 100 F. naphthenic mineral oil 100 parts "01240 SUS-at210 Fr naphthenic mineral oil.

This is a buttery, clear, homogenous calcium grease which performs well as a chassis lubricant.

Consistency:

At.60 strokes .325 at 77 F. .At.,5000 strokes 346 at 77 F. Thisisa break-down of about 6%. Dropping point by Ubbelohde method 200 F.

EXAMPLE NO. 3

Aluminum grease Into the grease kettle, while stirring, a slurry is made'ofz' 10 parts of 100 "SUSat 100 Fjnaphthenic'm'ineral oil.

7.5parts of aluminum soap made from a mixture of 50 parts. of oxidized hydrocarbons :and '50 parts of. high molecular. animal fattyacids; said fat mixture having asap; No.1of about 192.

Heat is slowly applied .until. a; firm gelatinous soap base results. Then:

107.5 parts of preheated,-heavy naphthenic-"mineral oil, viscosity 100 SUS-at 210 Fr'is slowly added-and the temperature stepby stepraised to about 380 Thistemperature is keptuntil all the heavy oil is incorporated'in. the grease. Th grease cannow be poured into containers and after a period of' about 48 hours is ready for use."

This .isa-smootlL-clear aluminum grease. easy to. handle -..in.v :lubrication .equipment. Field tests on chassis. slow. moving-.bearings andsas a. pres.- sure gun lubricant, .show satisfactory perform.-

ance.

consistencyaat 60=strolces830 at '17 F. I Dropping" point by: Ubbelohde methodabout EXAMPLE-NO; 4

Lithium grease Into the grease kettle --we charge:

2 parts of 100 SUS at 10091 naphthem'c mineral oil and.

2; parts of oxidized. hydrocarbons, having. a saponification number. of 1183.. Heat is slowly applied .whilestirring until. the oxidized hydro= carbons. dissolve inthemineral loili. To. this .is added a hot aqueous solution of the required amount of lithium .hydrate for complete saponification. The mass is brought .to.a .tem-

' peralniremf about 220 'F;' and .allowed to saponify. When-"most:ot the water evaporates the temperature is slowly increased .to about 380"Fi At *this temperature is added fparts of preheatedg100"SUS .at'100" naphth'enic .mineral-Loil. When the mass is ..com-' pletely homogenous the "grease 'may'b'e poured into containers at thistemperaturaor maybe stirred down to a lower temperature andpoured.

In either case the grease is tk'ettle finished "and can" be used as such:-

Theleonsistencynof this :greeseat .60 strokes; is

287 at 177% Kend a-15110000 strokes is 286 :at P77" Soiwerhave aa-smootlxillfiht colored..=.umtorm grease showing a break-down of 0% at 10,000 strokes. There is no sign of syneresis when stored at about 90 F. for a period of 9 months.

The dropping point of this grease by the Ubbelohde method is 375 F.

My invention is defined in the terms of the appended claims.

I claim:

1. A lubricant, comprising mineral oil, and a soap mixture formed by reacting a. saponifying agent with the product, as such, resulting from the oxidation of heavier aliphatic hydrocarbons varying in consistency from liquid to solid at normal temperature and which have been oxidized to produce a saponification number of at least 155, and forming with the mineral oil a solid to semi-solid grease of a substantially stable consistency.

2. A lubricant, comprising a major portion of mineral oil, and a minor portion of a soap mixture formed by reacting a saponifying agent with the product, as such, resulting from the oxidation of heavier aliphatic hydrocarbons varying in consistency from liquid to solid at normal temperature and which have been oxidized to produce a saponification number of at least 155, and with the mineral oil forming a solid to semi-solid grease of substantially stable consistency.

3. A lubricant, comprising a major portion of mineral oil, and a minor portion of a soap mixture formed by reacting a basic metal derivative with mixed products, as such, resulting from the liquid phase oxidation of heavier aliphatic hydrocarbons varying in consistency from liquid to solid at normal temperatures and which have been oxidized to the extent that the mixed products have a combined saponification number of at least 155 and forming with the mineral oil a solid to semi-solid grease of substantially stable consistency.

4. A lubricant, comprising a major portion of mineral oil, and a minor portion of a soap mixture formed by reacting a saponifying agent with a mixture of significant proportions of glycerides with the product, as such, resulting from the liquid phase oxidation of heavier aliphatic hydrocarbons varying in consistency from liquid to solid at normal temperatures and which have been oxidized to produce a saponification number of at least 155, the proportions of glycerides to oxidized product being related to the titer of the glycerides such that the titer of the mixture forms with the mineral oil a solid to semi-solid grease of substantially stable consistency.

5. A lubricant, comprising a major portion of mineral oil, and a soap mixture formed by reacting a saponifying agent with a mixture of sig- 6. nificant proportions of fatty acids derived from natural glycerides and the product, as such, resulting from the liquid phase oxidation of heavier aliphatic hydrocarbons varying in consistency from liquid to solid at normal temperatures and which have been oxidized to the extent of producing a saponification number of at least 155, the proportion of fatty acids to oxidized product being related to the titer of the fatty acids such that the titer of the mixture forms with the mineral oil a solid to semi-solid grease of substantially stable consistency.

6. A lubricant, comprising substantially of mineral oil, and a soap mixture formed by reacting a saponifying agent with the product as such resulting from the liquid phase oxidation of heavier aliphatic hydrocarbons varying in consistency from liquid to solid at normal temperatures and which have been oxidized to produce a saponification number of at least 155, and which forms with the mineral oil a semi-solid greas of substantially stable consistency,

7. A lubricant as described in claim 6 in which the saponifying agent consists of an alkali metal compound.

8. A lubricant as described in claim 6 in which the saponifying agent consists of an alkaline earth metal compound.

9. A lubricant as described in claim 6 in which the saponifying agent consists of a basic metal compound of the group consisting of lithium and sodium.

10. A lubricant as described in claim 6 in which the saponifying agent consists of a basic metal compound of the group consisting of barium, calcium, strontium, magnesium and zinc.

11. A lubricant as described in claim 6 in which th saponifying agent consists of a basic metal compound of aluminum.

12. A lubricant as described in claim 6 in which the saponifying agent consists of a basic metal compound of lead.

SABINE HIRSCH.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,700,056 James Jan. 22, 1929 2,012,252 Burwell Aug. 20, 1935 2,055,043 Nelson Sept. 22, 1936 2,058,237 Kaufman et al Oct. 20, 1936 2,137,494 Jolly Nov. 22, 1938 2,258,300 Morway Oct. 7, 1941 2,303,256 Camelford Nov. 24, 1942 2,391,019 Hirsch Dec. 18, 1945 2,391,236 Hirsch Dec. 18, 1945 

1. A LUBRICANT, COMPRISING MINERAL OIL, AND A SOAP MIXTURE FORMED BY REACTING A SAPONIFYING AGENT WITH THE PRODUCT, AS SUCH, RESULTING FROM THE OXIDATION OF HEAVIER ALIPHATIC HYDROCARBONS VARYING IN CONSISTENCY FROM LIQUID TO SOLID AT NORMAL TEMPERATURE AND WHICH HAVE BEEN OXIDIZED TO PRODUCE A SAPONIFICATION NUMBER OF AT LEAST 155, AND FORMING WITH THE MINERAL OIL A SOLID TO SEMI-SOLID GREASE OF A SUBSTANTIALLY STABLE CONSISTENCY. 